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Az storage blob sync using MD5 hash to calculate differences? RRS feed

  • Question

  • seems ‘az storage blob sync’ in the Azure CLI uses modified date to figure out if a file needs to be synced, even if the MD5 hash of a file is the same. Any way to use the hash to compare instead?
    Friday, August 30, 2019 8:23 PM

All replies

  • Firstly, apologies for the delay in responding here and any inconvenience this issue may have caused

    This is a bit dated but still you can refer to the suggestion mentioned in this link:

    You can use a third party tool RClone to compare the MD5 hashes of blobs https://rclone.org/azureblob/

    Disclaimer: This response contains a reference to a third-party World Wide Web site. 

    Microsoft is providing this information as a convenience to you. Microsoft does not control these sites and has not tested any software or information found on these sites; therefore, Microsoft cannot make any representations regarding the quality, safety, or suitability of any software or information found there. 

     

    As my understanding that: Azure Blob Storage support the MD5 hash calculation for blob automatically when putting blob, please see the content below of Get Blob Properties. If am wrong please correct me?

    Just for clarification: Can you use the Azcopy to do that, then append the --put-md5 flag to each copy command. That way, when the blob is downloaded, AzCopy calculates an MD5 hash for downloaded data and verifies that the MD5 hash stored in the blob's Content-md5 property matches the calculated hash.

    If the Content-md5 property value of a blob contains a hash, AzCopy calculates an MD5 hash for downloaded data and verifies that the MD5 hash stored in the blob's Content-md5 property matches the calculated hash. If these values don't match, the download fails unless you override this behavior by appending --check-md5=NoCheck or --check-md5=LogOnly to the copy command.

    You may also refer to the suggestion mentioned in this link which gives you more idea on this query

    Hope this helps!


    Monday, September 2, 2019 5:46 PM
    Moderator
  • @atwistinourfates  Is there any update on the issue?

    If the suggested answer helped for your issue, do click on "Mark as Answer" and “Vote as Helpful” on the post that helps you, this can be beneficial to other community members.

    Wednesday, September 4, 2019 5:20 AM
    Moderator
  • @atwistinourfates Just checking in to see if the above answer helped. If this answers your query, do click “Mark as Answer” and Up-Vote for the same, which might be beneficial to other community members reading this thread. And, if you have any further query do let us know.
    Monday, September 9, 2019 5:19 AM
    Moderator